Question

Should my multithreaded application with read only properties require locking? Since nothing is being written I assume there is no need for locks, but I would like to make sure. Would the answer to this question be language agnostic?

Without Lock:

Private Const m_strFoo as String = "Foo"
Public ReadOnly Property Foo() As String
    Get
        return m_strFoo.copy()
    End Get
End Property

With Lock:

Private Const m_strBar as String = "Bar"
Public ReadOnly Property Bar() As String
    Get
        SyncLock (me)
            return m_strBar.copy()
        End Synclock
    End Get
End Property

Edit: Added Const to Fields

Answer 1

Properly designed immutable objects are generally thread safe. The risk is that “properly designed” is a complicated subject – see Peter Veentjer’s treatment for an example of the pitfalls of immutable thread safety in Java.